To solve the problem of finding the number of grams of bromine that will completely react with 5.0 g of pent-1-ene, we need to perform stoichiometric calculations using the chemical reaction between pent-1-ene (C5H10) and bromine (Br2).
The balanced chemical equation for the reaction is: C5H10 + Br2 → C5H10Br2
This equation shows that 1 mole of pent-1-ene reacts with 1 mole of bromine.
Step 1: Calculate moles of pent-1-ene. Molar mass of C5H10 = (5×12) + (10×1) = 70 g/mol. Moles of C5H10 = 5.0 g / 70 g/mol = 0.0714 mol.
Step 2: Determine moles of bromine needed. According to the balanced equation, the mole ratio is 1:1, so moles of Br2 needed = 0.0714 mol.
Step 3: Calculate mass of bromine required. Molar mass of Br2 = 2×80 = 160 g/mol. Mass of Br2 = moles × molar mass = 0.0714 mol × 160 g/mol = 11.424 g.
Converting this to ×10–2 g: 11.424 g = 1142.4 × 10–2 g.
Step 4: Verify that the solution fits within the specified range. The calculated value in ×10–2 g is 1142.4, which, when rounded to the nearest integer, becomes 1143. Therefore, the number of grams of bromine that will completely react is 1143 × 10–2 g, which is within the expected range of 1143, 1143.
